Contact-tracing, testing & isolation are of utmost importance, said Dr Naresh Trehan, Chairman & MD, Medanta. People should be penalised for not wearing a mask, he added. Relevantly, India's biggest single-day surge in coronavirus cases with 24,879 new infections reported in the last 24 hours has taken the country's tally to 7,67,296 cases, the Union Health Ministry said this morning. According to the official figures, around 4.76 lakh patients have recovered since the beginning of the pandemic; 21,129 deaths linked to the illness have been recorded.